Five studies examined whether receiving gratitude expressions from a romantic partner can buffer insecurely attached individuals from experiencing low relationship satisfaction and commitment. In Study 1, the negative associations between attachment avoidance and both satisfaction and commitment were weaker among individuals who perceived that their partner expressed gratitude more frequently. The same pattern was found with attachment anxiety and satisfaction. Study 2 showed that among individuals who perceived high (vs. low) levels of gratitude expressions from the partner, both attachment dimensions were less strongly related to the belief that the partner is low in communal strength, which, in turn, was associated with greater satisfaction and commitment. In Studies 3-5, we examined whether perceptions or a partner's actual gratitude expression can have benefits on insecurely attached individuals' daily satisfaction. Our results indicated that perceived, rather than a partner's self-reported, gratitude expressions were critical to buffering insecurely attached individuals' daily dissatisfaction. Study 5 also provided evidence for long-term benefits of perceiving a partner's gratitude expressions on avoidantly attached individuals' relationship. Perceiving high levels of a partner's gratitude expressions on average enhanced avoidantly attached individuals' feelings of being cared for by the partner 3 months later, which were associated with greater satisfaction and commitment. Results from our meta-analysis indicated that benefits of perceiving a partner's gratitude expressions may be specific to buffering the negative effects of attachment avoidance on satisfaction. Overall, our findings highlight the powerful function of gratitude in insecurely attached individuals' romantic relationships. (PsycINFO Database Record (c) 2019 APA, all rights reserved).